Experimental Study on Mechanical Properties of Seawater Sea-Sand Recycled Concrete Under Sulfate Attack

Abstract

The preparation of seawater sea-sand recycled concrete (SSRAC) by combining seawater, sea-sand and recycled coarse aggregate is of great significance for the utilization of marine resources and environmental protection in China. The sulfate corrosion test in this paper uses dry wet cycle to simulate the alternating dry wet environment, and compares the ordinary concrete (OC) and freshwater river sand recycled concrete (RAC) to study the mechanical property deterioration characteristics of SSRAC in dry–wet cycle (30d, 60d, 90d, 120d). The results show that with the increase of the dry–wet cycle, the apparent damage of SSRAC gradually extends from the diagonal to the periphery, and finally the cracks spread all over the whole. The mass, strength and strength corrosion resistance coefficient of SSRAC show the same law as OC and RAC, which increase first and then decrease. The resistance of SSRAC to sulfate attack is lower than OC and slightly higher than RAC, and the strength corrosion resistance coefficient is lower than 75% at 120 times of dry–wet cycle.